title: The role and prognostic value of apoptosis in colorectal carcinoma.
abstract: BACKGROUND
  Alterations to apoptosis are a common occurrence in human tumours. The aim of our study was to determine the influence of apoptotic variations on the carcinogenesis and prognosis of colorectal carcinomas (CRCs).
  
  
  METHODS
  A TUNEL assay was performed on archival material from 103 colorectal carcinomas, 26 adenomas and 20 samples of normal epithelia.
  
  
  RESULTS
  The number of apoptotic cells was higher in CRCs (1.09 ± 0.13) than in adenomas (0.38 ± 0.23, p = 0.059) and normal epithelium (0.06 ± 0.04, p = 0.001). In addition, the apoptotic index (AI) was greater in metastatic disease (stage IV) than in other stages (p = 0.017). No relationship was found between apoptotic rates and age, gender or tumour grade. However, patients with tumours that showed higher AI values had a significantly lower disease-free survival (DFS) and overall survival (OS) than those with tumours that had lower AIs (p = 0.020 and p = 0.027). In a multivariate Cox proportional hazards model, AI remained a significant independent predictor of survival.
  
  
  CONCLUSIONS
  We conclude that disregulated apoptosis is an important event during CRC development and progression. Higher AIs are associated with more aggressive tumours and a poorer prognosis for patients with CRC.
authors.affiliation: Red de Investigacion en Servicios de Salud (REDISSEC), Spain. mredondo@hcs.es.
authors.forename: Julia
authors.initials: J
authors.lastname: Alcaide
authors.forename: Rafael
authors.initials: R
authors.lastname: Funez
authors.forename: Antonio
authors.initials: A
authors.lastname: Rueda
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Perez-Ruiz
authors.forename: Teresa
authors.initials: T
authors.lastname: Pereda
authors.forename: Isabel
authors.initials: I
authors.lastname: Rodrigo
authors.forename: Rafael
authors.initials: R
authors.lastname: Coveñas
authors.forename: Miguel
authors.initials: M
authors.lastname: Muñoz
authors.forename: Maximino
authors.initials: M
authors.lastname: Redondo